Convert //ios from scoped_ptr to std::unique_ptr.

ios/chrome/browser/favicon/ios_chrome_favicon_loader_factory.mm

Index: ios/chrome/browser/favicon/ios_chrome_favicon_loader_factory.mm
diff --git a/ios/chrome/browser/favicon/ios_chrome_favicon_loader_factory.mm b/ios/chrome/browser/favicon/ios_chrome_favicon_loader_factory.mm
index 253820b7fab45de22146cf8fb85a3acbc69a21a3..dc54bf37ef16e274cd71c84df161c93e5fff71af 100644
--- a/ios/chrome/browser/favicon/ios_chrome_favicon_loader_factory.mm
+++ b/ios/chrome/browser/favicon/ios_chrome_favicon_loader_factory.mm
@@ -4,6 +4,7 @@
 
 #include "ios/chrome/browser/favicon/ios_chrome_favicon_loader_factory.h"
 
+#include "base/memory/ptr_util.h"
 #include "base/memory/singleton.h"
 #include "components/keyed_service/core/service_access_type.h"
 #include "components/keyed_service/ios/browser_state_dependency_manager.h"
@@ -37,11 +38,12 @@ IOSChromeFaviconLoaderFactory::IOSChromeFaviconLoaderFactory()
 
 IOSChromeFaviconLoaderFactory::~IOSChromeFaviconLoaderFactory() {}
 
-scoped_ptr<KeyedService> IOSChromeFaviconLoaderFactory::BuildServiceInstanceFor(
+std::unique_ptr<KeyedService>
+IOSChromeFaviconLoaderFactory::BuildServiceInstanceFor(
     web::BrowserState* context) const {
   ios::ChromeBrowserState* browser_state =
       ios::ChromeBrowserState::FromBrowserState(context);
-  return make_scoped_ptr(
+  return base::WrapUnique(
       new FaviconLoader(ios::FaviconServiceFactory::GetForBrowserState(
           browser_state, ServiceAccessType::IMPLICIT_ACCESS)));
 }